A technique of fastening an object to be fastened using a fastener (a fastening component) such as bolt and rivet is used for assembling an aircraft etc. A rivet applying apparatus for fastening the object to be fastened using the rivet is known.
An automatic riveting device disclosed in Patent Literature 1 includes a riveter main body having a mechanism to drive the rivet to a workpiece. The riveter main body has a C-shape to sandwich the workpiece in the vertical direction. An upper head portion is provided at an end of the upper side of the riveter main body. A die is provided at an end of the lower side of the riveter main body.
FIG. 1 is for indicating above mentioned upper head portion 351. The upper head portion 351 is movable in directions indicated by the arrows using a hydraulic cylinder 352. A vertically movable drill spindle 353, a vertically movable rivet caulking jig 354 and a vertically movable shaving cutter 355 are arranged along a straight line parallel to the direction indicated by the arrows at the lower surface of the upper head portion 351, which is the position facing the upper surface of the workpiece 304. A drill 356 is mounted on the drill spindle 353. After the workpiece 304 is set, the drill spindle 353 is lowered to form a rivet hole 304a in the workpiece 304. Then, the hydraulic cylinder 352 moves the rivet caulking jig 354 to the position where the drill spindle 353 was located so far. Next, the rivet caulking jig 354 is lowered while holding the rivet R to insert the shank portion of the rivet R into the rivet hole 304a. Further, the rivet R is pressed by both the die formed on the lower side end of the riveter main body and the rivet caulking jig 354. As a result, the driving the rivet R has been completed. Note that the shaving cutter 355 is used for removing the head of the rivet R.
Patent Literature 2 and Patent Literature 3 disclose other riveting devices.
In recent years, cases in which component made of composite material such as fiber reinforced plastic in place of component made of metal is used are increasing. For example, a lot of composite material components have come to be used for the aircraft.
Referring to FIGS. 2 to 7, a method of manually fastening the composite material component to be fastened will be explained.
As shown in FIG. 2, the workpiece 100 as the object to be fastened includes a plurality of composite components 51 and 52 in a stacked state. A hole 100a with a countersink which penetrates from one side of the workpiece surface 100b to the other side of the work piece surface 100c is formed. The countersink portion of the hole 100a is disposed on the surface 100b side. The workpiece 100 has a countersink wall 100d surrounding the countersink portion of the hole 100a. After the hole 100a with the countersink is formed, the workpiece 100 is cleaned and burrs generated during the formation of the hole 100a with the countersink are removed.
FIG. 3 is for indicating a fastener 25 as a fastening component for fastening the workpiece 100. The fastener 25 includes a flat head bolt 20 and a sleeve 40. The flat head bolt 20 includes a head portion 21, a cylindrical portion 22, and a threaded portion 23. The head portion 21 has a head upper surface 21a and a head side surface 21b. The head side surface 21b is formed in a conical surface. The cylindrical portion 22 is disposed between the head portion 21 and the threaded portion 23. The cylindrical portion 22 is not formed threads. The threaded portion 23 has an end surface 23a. The head upper surface 21a and the end surface 23a are arranged at both ends in the axial direction of the fastener 25. The sleeve 40 is placed to cover the cylindrical portion 22. A portion of the cylindrical portion 22 close to the head portion 21 is exposed from the sleeve 40. The sleeve 40 includes a flat portion 41 disposed on the head portion 21 side and a cylindrical portion 42 disposed on the threaded portion 23 side. The flat portion 41 is formed in a conical shape.
As shown in FIG. 4, the fastener 25 is inserted into the hole 100a with the countersink until the flat portion 41 comes in contact with the countersink wall 100d. In a state that the flat portion 41 is in contact with the countersink wall 100d, the head portion 21 protrudes from the surface 100b and the threaded portion 23 protrudes from the surface 100c. 
As shown in FIG. 5, the fastener 25 is driven by repeatedly applying impact force to the head upper surface 21a using an air hammer 200.
As shown in FIG. 6, the impact force is repeatedly applied until the fastener 25 is seated on the workpiece 100. That is, the impact force is repeatedly applied until the head portion 21 comes in contact with the countersink wall 100d via the flat portion 41.
As shown in FIG. 7, the composite material component 51 and the composite material component 52 are fastened by mounting a nut 30 on the threaded portion 23.